The rate at which hydrocarbons are produced from wellbores in subterranean formations is often limited by wellbore damage caused by drilling, cementing, stimulating, and producing. As a result, the hydrocarbon drainage area of wellbores is often limited, and hydrocarbon reserves become uneconomical to produce sooner than they would have otherwise, and are therefore not fully recovered. Similarly, increased power is required to inject fluids, such as water and CO2, and to dispose of waste water, into wellbores when a wellbore is damaged.
Formations may be fractured to stimulate hydrocarbon production and drainage from wells, but fracturing is often difficult to control and results in further formation damage and/or breakthrough to other formations.
Tight formations are particularly susceptible to formation damage. To better control damage to tight formations, lateral (namely, horizontal) completion technology has been developed. For example, guided rotary drilling with a flexible drill string and a decoupled downhole guide mechanism has been used to drill laterally into a formation, to thereby stimulate hydrocarbon production and drainage. However, a significant limitation of this approach has been severe drag and wear on drill pipe since an entire drill string must be rotated as it moves through a curve going from vertical to horizontal drilling.
Coiled tubing drilling (CTD) has been used to drill lateral drainage holes, but is expensive and typically requires about a 60 to 70 foot radius to maneuver into a lateral orientation.
High pressure jet systems, utilizing non-rotating nozzles and externally rotating nozzles with fluid bearings have been developed to drill laterally to bore tunnels (also referred to as holes or boreholes) through subterranean formations. Such jet systems, however, have failed due to the turbulent dissipation of jets in a deep, fluid-filled borehole, due to the high pressure required to erode deep formations, and, with respect to externally rotating nozzles, due to impairment of the rotation of the nozzle from friction encountered in the formation.
Accordingly, there is a need for methods and systems by which wellbore damage may be minimized and/or bypassed, so that hydrocarbon drainage areas and drainage rates may be increased, and the power required to inject fluids and dispose of waste water into wellbores may be reduced.